Slant
<p>
Fill in a diagonal line in every grid square so that there are no
loops in the grid, and so that every numbered point has that many
lines meeting at it.
<p>
Left-click in a square to mark it with a <code>\</code>; right-click
to mark it with a <code>/</code>. Keep clicking in a square to
cycle it between <code>\</code>, <code>/</code> and empty.
